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Postini Declares Shift in Spam Battle

E-mail security and management provider Postini declared this week that its method of blocking spam e-mails based on IP addresses is proving an effective complement to content filtering.

The company claims it is currently blocking 53 percent of all e-mail connections without the need for message scanning. For a managed services provider with 10.75 billion SMTP requests in June, that takes a big load off the scanning engine. IP addresses cannot be spoofed the way that messages can.

"The spam story today is one of connections, not content," Postini founder Scott Petry said in a statement. "Spam content has been changing yet again during the last six months, making it far harder for content filters to detect."

According to Postini, a key weapon in the war against spam is to move up to the SMTP connection. "Since we can't get behind their firewalls, the best thing we can do is watch the spammer's behavior at the connection layer and preemptively shut them down before they do any harm," Petry said.

Clearly the IP address approach isn't a cure-all. Of the remaining 47 percent of messages that came through Postini's system, 76 percent was identified by Postini scanners as spam.